Dynamic modelling of retrogressive landslides with emphasis on the role of clay sensitivity

This paper presents a detailed numerical study of the retrogressive failure of landslides in sensitive clays. The dynamic modelling of the landslides is carried out using a novel continuum approach, the particle finite element method, complemented with an elastoviscoplastic constitutive model. The multiwedge failure mode in the collapse is captured successfully, and the multiple retrogressive failures that have been widely observed in landslides in sensitive clays are reproduced with the failure mechanism, the kinematics, and the deposition being discussed in detail. Special attention has been paid to the role of the clay sensitivity on each retrogressive failure as well as on the final retrogression distance and the final run‐out distance via parametric studies. Moreover, the effects of the viscosity of sensitive clays on the failure are also investigated for different clay sensitivities.     

RECENT TECTONIC DEFORMATION ANOMALY AND EARTHQUAKES IN GANSU-NINGXIA-QINGHAI AREA

1　IntroductionAccordingtogeologicalstructure ,theGansu Ningxia Qinghaiareabelongstothenortheastmar ginofQinghai Tibetblock .Thisareahasbeenpaidmuchattentionby geo specialistsinChinaandabroadbecauseofitssignificanttectonicmovement,itsintensiveseismicity ,anditsimportanceinearth quakehazardmitigation .IntheDevelopmentPro gramonNationalKeyBasicResearchesundertheProject“MechanismandPredictionofContinentalStrongEarthquakes”,themechanismsofcontinen talstrongearthquakesarestudied ,usinghypo…     

CHANGE OF NUTRIENT IMPORT AND EXPORT IN PROCESS OF RAINFALL IN AILAO MOUNTAIN OF YUNNAN PROVINCE

ＣＨＡＮＧＥ　ＯＦ　ＮＵＴＲＩＥＮＴ　ＩＭＰＯＲＴ　ＡＮＤ　ＥＸＰＯＲＴ　ＩＮ　ＰＲＯＣＥＳＳ　ＯＦ　ＲＡＩＮＦＡＬＬ　ＩＮ　ＡＩＬＡＯ　ＭＯＵＮＴＡＩＮ　ＯＦ　ＹＵＮＮＡＮ　ＰＲＯＶＩＮＣＥＧａｎＪｉａｎｍｉｎ（甘健民）；ＸｕｅＪｉｎｇｙｉ（薛敬意...     

Mobile Agent系统结构及其关键技术

Mobile Agent技术是一门新兴的技术,具有移动性、智能性和异步计算的特点,已成为计算机网络和分布式系统最具活力的发展方向.现对Mobile Agent的概念、系统结构及其关键技术进行了分析和探讨.     

冬半年青藏高原低涡发生发展的天气学分析

本文针对冬半年高原低涡几个不同源地的低涡生成背景,着重分析500hpa环流场,指出:地形对低涡生成是非常重要的条件,但一定范围内有利的环境流场也是低涡生成不可缺少的外部条件。并给出了不同涡源区有利于低涡发生,发展的500hpa环流形势。     

青藏块体东北缘断层形变与中强地震

对祁连山－海原断裂带近期断层形变特征进行了初步研究，发现多场地，大范围的断层活动异常是中等强度地震发生的显著背景，并且往往与大陆地震活动的阶段性总体状况相呼应；区域形变存在明显的特征量，包括特征形态和特征时间，同一场地在不同地震前的异常特征具有重复性，但会受到背景差异显著的不同地震的影响，目前形变状况表明研究区仍具有发生中强地震的地壳运动背景。     

The Variabilities of the Soft and Hard X—ray Components of NGC 7314 and NGC 7582 and the Distribution of Absorbing Matter in Type Ⅱ AGNs

ASCA observations of the two Type Ⅱ AGNs,NGC7314 and NGC 7582,show clear variations in the broad X-ray band(0.4-10keV)on short timescales-10^4s.Spectral analysis indicates that they bot have an absorbed hard X-ray component and an unabsorbed soft“excess” component.To clarify the origin of the latter,we made a cross-correlation analysis of the two components.The results show that,for NGC7314,the soft X-ray variability is proportional to that of the hard X-ray component.This indicates that the active nucleus of NGC 7314 must be partially covered and so the soft emission is a “leaking” of the variable hard component.For NGC 7582,there is no detectable variability in the soft component, although there is a definite one in the hard component.This indicates that the variable nucleus of NGC 7582 must be fully blocked by absorbing matter,and the soft emission is most likely the scattered component predicted by the AGN unified model.     

从ROSAT数据中寻找河内X射线暂现源

从ＲＯＳＡＴ巡天和定点观测结果的对比出发，发现了几个低银纬的巡天源表中的Ｘ射线源在定点观测中没有出现．本文计算了在这些位置的定点观测中出现点源的流强上限，发现比巡天源表中这些源的流强值低很多，这表明它们的流强变化很大，可能是Ｘ射线双星系统中的一类———Ｘ射线暂现源．     

拉格朗日插值法在渔业资源评估上的应用

应用拉格朗日插值法拟合鱼类体长与体重之间的函数关系 ,使用计算机VB语言进行编写程序 ,与常用的线性回归法、Ricker法进行比较 ,得出体长与体重的关系式为Pn(x) =∑nk=0yklk(x)=∑nk=0(∏nj=0j≠kx-xjxk-xj)yk 。     

Modelling the April 15 spectrum of Supernova 1993 J

We present the modeling of the ultraviolet and optical spectra obtained simultaneously on 1993 April 15 with the HST and at Lick Observatory. A Monte Carlo code is employed in the modeling and a comparison is made between models reported by different groups. With an atmosphere similar to the Sun in chemical composition, the observed spectral lines are well reproduced by a power law density structure of index around 20 except the strong H and HeI λ5876 lines which have peculiar absorption profiles. The photospheric velocity is found to be 9500 km/s and the blackbody temperature of the spectrum is 7990 K. For H and HeI λ5876, we suggest a two-component density structure which has a smoother layer located immediately outside the steeply decreasing inner envelope. The power law indices are most probably 20 and 3, respectively, with the transition point at about 13 000 km/s. In addition, this outer smooth layer serves to flatten the far UV spectrum as observed.